I made a cuple of small changes but I am not sure if it works...:
Code:

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//defines
define Health, skill1;
define WSpeed, skill2;
define RSpeed, skill3;
define JumpHeight, skill4;
define AttackSpeed, skill5;

//Vars
var move_vec[3] = 0,0,0; 
var idle_percent = 0;
var walk_percent = 0;

//Debug Tekst
bmap bmpGrond1 = "sand.pcx";   //Grass Grond
string str_type2 = "Grass"; // Zand Grond
//Water Grond
//Modder Grond

//Lettertype
font fnt_century12 = <Centur12.pcx>,16,20; // Century12 font

//Grond Panels
panel pnl_Grond1

{

	bmap = bmpGrond1;

	layer = 21;

	pos_x = 0;

	pos_y = 0;

	//on_click = get_off_grond1;

	flags = overlay,transparent,refresh;

}

text txt_Grond2

{

	pos_x = 0;

	pos_y = 65;

	layer = 15;

	font fnt_century12;

	string str_type2;
	

}
///Einde Debug Scripts

function check_keys()
{
	move_vec[0] = (key_w - key_s)*15 *time;
	move_vec[1] = (key_a - key_d)*10 *time;
	
	If (move_vec[0] == 0  && move_vec[1] == 0)
	{
		idle_percent = (idle_percent +5*time)%100;
		ent_animate(me,"idle",idle_percent,ANM_CYCLE);
	}
	else
	{
		walk_percent = (walk_percent + sign(move_vec[0])*5*time)%100;
		ent_animate(player,"walk",walk_percent,ANM_CYCLE);
	}
	
	move_mode = IGNORE_YOU + IGNORE_PASSABLE + IGNORE_PUSH + ACTIVATE_TRIGGER + GLIDE;
	ent_move(move_vec,NULLVECTOR);
	
}

function Check_Ground()
{
	c_trace(my.x, vector(my.x, my.y, my.z -10000),IGNORE_ME | IGNORE_SPRITES | IGNORE_PASSENTS | IGNORE_PASSABLE | IGNORE_MODELS | SCAN_TEXTURE);
	if(str_stri(tex_name, "grass"))
	{
		pnl_Grond1.visible = on;
	}else
	{
		pnl_Grond1.visible = off;
		if(str_stri(tex_name, "sand"))
		{
			txt_Grond2.visible = on;
		}else
		{
			txt_Grond2.visible = off;
		}
	}
}

//skill1: Health 100
//skill2: WalkingSpeed 2
//skill3: TurningSpeed 10
//skill4: JumpHeight 10
//skill5: AttackSpeed 10
action Speler_Beweging()
{
	player = my;
	camera.genius = my;
	
	c_setminmax(me);
	
	while(my.skill1)
	{
		check_keys();
		check_ground();
		
		wait(1);
	}	
}

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